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METHODS OF MANUFACTURE.
phorus may be reduced to .02 per cent., but by having 2 per cent, of manganese the phosphorus may be worked down to 0.005 per cent, in the steel. Such a low content is not unusual in America, but the pig-iron at Kladno carries 1.5 per cent, of phosphorus. The Ber-trand Thiel process would seem to be most applicable to pig-irons containing a considerable quantity of phosphorus, for the slag from the primary furnace is then of considerable value as a fertilizer. In the northern part of the United States, where there are no pig-irons containing high percentages of phosphorus, this primary slag would be of no value, but in the South or in Cape Breton it might be an important by-product.
TABLE XII-F. Practice at Kladno. Private Communication, February, 1901.
	Composition of Metal, Per cent.					Composition of Slag.  Per cent.		
	C	Si	Mn	P	8	SiO,	P.O.	Fe
Heat A Primary furnace : At charging .......................... 1 hr. after charging .................... 1 hrs. 20 mln. after charging, transferred to second furnace ............ Secondary furnace : 1 hr. after transfer ....... < ............. a hrs. after transfer, tapped ............ Heat B Primary furnace : At charging ............................	3.50 3.45 2.50 .35 .15 3.50 3.50 2.70 .31 .16	.50 .15 .04. .02 .02 1.30 .31 .01 tr tr	.47 .42 .10 .05 .32 .39 .20 .06 .10	1.35 .93 .09 .02 .01 1.25 .99 .17 .02 .02	,.025 tr tr tr tr	'ib'.oo 19.16 14.66 13.00 *26'. 66 24.33 13.33 11.43	'isle? 18.88 9.70 4.99 'io.37 15.83 14.40 5.67	*ii'.20 6.00 18.00 13.50 'is.oo 6.00 11.00 15.75
3 hrg. 10 min. after charging, transferred to second furnace ............								
Secondary furnace :								
								
								
SEC. Xlle.The heat absorbed ly the reduction of ore.-It has been stated in Section XIIc that the reduction of iron ore by melted pig-iron does not create heat, but absorbs it, and this can be proven by finding the heat produced by the oxidation of the silicon and carbon, and the heat absorbed in the dissociation of the iron oxide. Inasmuch as it has been stated that Mr. Talbot is in